荧光免疫定量法即时检测谷物中黄曲霉毒素B1

目的 基于时间分辨荧光免疫层析技术，研制快速定量检测试纸条，用于粮谷物中黄曲霉毒素B1的检测。方法 以荧光微球为标记物，采用DNP独立质控体系和竞争法检测原理，构建了粮谷物中黄曲霉毒素B1荧光免疫定量即时检测（point-of-care testing ，POCT）方法。评价其准确度、重复性、特异性、与仪器确证方法符合度。结果 该方法最适条件为：pH7.8硼酸盐（BB）活化，pH7.5磷酸盐（PB）偶联，微球抗体质量比为5:4，抗原抗体质量比为50:1。检测限在0.299 ng/g -0.997 ng/g之间，定量限在0.544 ng/g -2.663 ng/g。代表性样本准确度为92.2%-111%，重复性为3.2%-7.5%。除与黄曲霉毒素B2有交叉反应（6.1%），与其他类似物无（<0.1%）。该法检测结果与仪器确证法一致性好，在-12.5%—15.9%之间。结论 提供了一种准确、快速、定量、灵敏、便捷、适合现场检测粮谷物中黄曲霉毒素B1的时间分辨荧光免疫检测试纸条。

Point-of-care testing of aflatoxins B1 in cereals by fluorescence immunoquantitative assay

Objective Based on time-resolved fluorescence immunochromatography, a rapid quantitative test strip was developed for the detection of aflatoxin B1 in cereals.Methods A fluorescence quantitative point-of-care testing (POCT) method for aflatoxin B1 in cereals was established by using fluorescent microspheres as markers.It adopted DNP independent quality control system,and was based on the detection principle of competition method.The accuracy, repeatability, specificity and conformity with the instrument confirmation method were evaluated.Results The optimum conditions for the method were as follows: pH7.8 borate (BB) activation, pH7.5 phosphate (PB) coupling, microsphere antibody mass ratio of 5:4, antigen antibody mass ratio of 50:1. The limit of detection was 0.682 ng/g - 0.997 ng/g, and The limit of quantitation was 1.823 ng/g- 2.663 ng/g. The accuracy of representative samples was 92.2%-111%, and the repeatability was 3.2%-7.5%. Except for cross-reaction with aflatoxin B2 (6.1%), there was no cross-reaction with other analogenates (<0.1%). The deviation between the results of this method and the instrument confirmation method is between -12.5% and 15.9%, and the consistency is good. Conclusion This paper provides an accurate, rapid, quantitative, sensitive and convenient time-resolved fluorescence immunoassay strip suitable for field detection of aflatoxin B1 in cereals.